Ultra Thin PM Type LPM

Abstract

We have studied a thin actuator for application in an ultra thin optical disk drive. First, a simple calculaton method of thrust using a permeance method is described. Then using this method, the thrust is estimated for a permanent magnet type linear pulse motor (PM type LPM) and a voice coil motor (VCM) which is generally applied to the optical disk drive.
This estimation shows that acceleration of the PM type LPM is 1.6 times larger than that of the VCM when the actuator thickness is smaller than 15mm. We fabricated a 6-mm-thisk PM type LPM having a thrust constant of 0.78 N/A and a maximum thrust of 0.5 N.